Chait began working at The New Republic in 1995. In January 2010, The New Republic replaced The Plank, TNR's group blog, with the Jonathan Chait Blog. His writing has also appeared in The New York Times, The Wall Street Journal, Slate and Reason. He took over The New Republic's TRB column from Peter Beinart in March 2007. His columns from 2008 are a finalist for the National Magazine Award, in the category of best commentary.[citation needed]

On March 16, 2009, Chait appeared on Comedy Central's The Colbert Report to counter conservative arguments that the New Deal was a failure.[2] The impetus for that appearance was an article he wrote for The New Republic called "Wasting Away in Hooverville".[3]

Chait appears in The Rivalry, a 2007 HBO documentary about the history and culture of the Michigan-Ohio State football rivalry. Chait joined the staff of New York magazine on September 6, 2011, leaving his post of Senior Editor at The New Republic.[4] He explained the move as follows: "Obviously I love TNR and had no plans to leave, but the opportunity at New York was irresistible. Everybody who works there raves about it, and my friends in journalism have noticed for a while it's become phenomenal — 'the best magazine in America', as one editor friend of mine told me".[5]

Chait usually writes about domestic politics and policy. Many of his writings are critiques of what he perceives to be illogical positions taken by conservatives. A self-described liberal hawk,[6] but has written pieces critical of left-wing figures such as Naomi Klein,[7] and wrote a TNR cover article condemning the state of Delaware.[8]

He drew considerable attention with his "Case for Bush Hatred", in which he defended his dislike not only of Bush's policies but also his personality and mannerisms of the then-president's persona.[9]

Chait occasionally writes about sports, particularly stories involving his alma mater, the University of Michigan. He strongly criticized the editorial staff of the Detroit Free Press following a controversial article by Michael Rosenberg that alleged systematic infractions of NCAA rules by the Michigan football program under former head coach Rich Rodriguez. Chait suggested Rosenberg's editor should "lose his job" and called the investigation's methodology "journalistic malpractice".[10]

Chait wrote an article for New York Magazine (January 26-February 8, 2015 edition) on political correctness, which he labeled “a system of left-wing ideological repression”, citing examples from academia and social media. This provoked a backlash online.[13]